irrational fear of flying

[thollandpe]

Yes.

Pretty much every airplane you can imagine since about 1970.

Think 777s or 787s or Airbus of all models are flown with cables and pulleys? Think again.

My question is different from fly-by-wire. I remember the Airbus A320 trimming the trees at a French airshow in the 80's, that crash was blamed on pilot error. That was the auspicious launch of fly-by-wire on commercial aircraft.

Have there been other commercial airliners with unstable traits or relaxed static stability? If that's the same answer, thanks for the clarification.

[Saab2000]

My question is different from fly-by-wire. I remember the Airbus A320 trimming the trees at a French airshow in the 80's, that crash was blamed on pilot error. That was the auspicious launch of fly-by-wire on commercial aircraft.

Have there been other commercial airliners with unstable traits or relaxed static stability? If that's the same answer, thanks for the clarification.

I don't know specifically, but my understanding is that the SAAB2000, from which I drew my online name and in which I started my career, had some significant center-of-gravity issues that were resolved with fly-by-wire elevators. As it happens, the rudder on the SB-20 is also FBW. This aircraft was produced in only relatively small numbers but it was certified for passenger airline flying by responsible aviation authorities.

I am not an engineer so I really can't answer your question but I'm inclined to think that MCAS by itself is not a bad thing. The bad thing is when it overrides pilot inputs, can't be fully disabled or when it leads to an area of the flight envelope which is unrecoverable. It would surprise me if the 737 MAX series was the only airplane with a trim system designed to compensate for some potential inherent instability in some part of the CG range. If it were only a CG issue Boeing could simply add mass somewhere in the airframe and call it good. I suspect it's a bit more complicated than that. Having the engines slung below the wing and in front of the wing will create forces that need to be trimmed. The already existing "speed trim" on the 737 is an example of this.

We still need to wait for more facts. Meanwhile, the grounding of the airplanes is a good thing because they must be safe for crews and passengers and this safety needs to be pretty much verified in near-absolute terms for public confidence.

I suspect they won't fly again until summer, at least.

[busdriver1959]

There are some new bits of information coming out about the latest max crash. As Saab mentioned, the crew did the right thing and shut off the electric trim. At some point they turned it back on because they were having trouble with manual trim. Somewhere else on the internet, a 73 pilot points out that manual trim can get very hard to move due to friction/ binding in the system when high air loads put pressure on the various components. If that's the case, that points the finger back at Boeing. However, does the 73 Max trim wheel have a fold out handle like we had on the 72? Maybe Saab will answer. I think both aircraft use the same trim wheel. If so, the handle would allow two handed operation and a much improved ability to overcome the binding. There aren't any reports so far that discuss how the crew went about trying to move the manual trim though. Another question I still have is, how did the airspeed get that high? The pitch and power settings for unreliable airspeed, especially in the area of an airfield that's already up at 8000 feet, shouldn't let the airspeed get very high. There's a lot going on at that time though. Stick shaker going off, stab trim running, unreliable airspeed on one side of the cockpit displays. That's a lot to sort through. These guys flew for 6 minutes. Lion Air for 11 minutes. Ther's time there to come up with a plan. It's not easy to come up with a plan in a situation that's complicated by multiple failures/problems. A good read is "QF 32". It's the story written by the captain of the Quantas A380 with the uncontained engine failure that took out a whole bunch of other systems on the airplane. At one point he simply had to shift gears and quit trying to figure out what systems were lost. That didn't matter to him any more. He figured out what he still had and came up with a plan to use those systems to get back on the ground safely.
It'll be a while before a complete report comes out. It'll be interestiong to see the whole story of the crew's responses in this case.

[Saab2000]

There are some new bits of information coming out about the latest max crash. As Saab mentioned, the crew did the right thing and shut off the electric trim. At some point they turned it back on because they were having trouble with manual trim. Somewhere else on the internet, a 73 pilot points out that manual trim can get very hard to move due to friction/ binding in the system when high air loads put pressure on the various components. If that's the case, that points the finger back at Boeing. However, does the 73 Max trim wheel have a fold out handle like we had on the 72? Maybe Saab will answer. I think both aircraft use the same trim wheel. If so, the handle would allow two handed operation and a much improved ability to overcome the binding. There aren't any reports so far that discuss how the crew went about trying to move the manual trim though. Another question I still have is, how did the airspeed get that high? The pitch and power settings for unreliable airspeed, especially in the area of an airfield that's already up at 8000 feet, shouldn't let the airspeed get very high. There's a lot going on at that time though. Stick shaker going off, stab trim running, unreliable airspeed on one side of the cockpit displays. That's a lot to sort through. These guys flew for 6 minutes. Lion Air for 11 minutes. Ther's time there to come up with a plan. It's not easy to come up with a plan in a situation that's complicated by multiple failures/problems. A good read is "QF 32". It's the story written by the captain of the Quantas A380 with the uncontained engine failure that took out a whole bunch of other systems on the airplane. At one point he simply had to shift gears and quit trying to figure out what systems were lost. That didn't matter to him any more. He figured out what he still had and came up with a plan to use those systems to get back on the ground safely.
It'll be a while before a complete report comes out. It'll be interestiong to see the whole story of the crew's responses in this case.

Yes, it still has the fold-out handle.

I’ve used it on the ground but never in the air. Having never used it in flight I don’t know how the forces change.

I suspect next year’s training program at my carrier will include a lot of hand flying and trim issues, including using this fold-out handle.

[SteveP]

I suspect next year’s training program at my carrier will include a lot of hand flying and trim issues, including using this fold-out handle.

I sure bet that this is true.

[rwsaunders]

Thinking of you guys...flying from Heathrow to Venice late this evening and the pilot aborted the landing while the gear was down...always interesting. He told us later that the ATC’s diverted us at the last minute due to bad weather/runway issues. First we were supposed to divert to Bergamo and then we finally landed in Milan, where I type this post from 10C. Hope this 2hr flight doesn’t turn into 5hrs as we’ve been waiting on the runway for over an hour for a bus and they made me check luggage as I have no status on British Airways. First world problem I know.

[SteveP]

Good luck.

My favorite country but I have had a couple of unusual flight occurrences there.
" Bad weather flight cancellation" out of Florence...
We were in Florence heading back to Munich... the plane never arrived.
The weather was fine... some breeze, a few drops of rain. Nothing.

Another page on this Max thing seems to be turned every day.
Big story. Shakespeare wrote about it..
" There's something rotten in Denmark..."
We aren't sure yet where Denmark is yet.

[rwsaunders]

Still haven’t heard from BA Steve, as they essentially abandoned a plane load of people at the Milan airport at 1:00am, eventually loading 7 passengers at a time into a van for a ride to a hotel...no rebooked flight news. The skeptic in me booked a hotel in Milan, took an 80 euro cab ride into the city at 2:30 am and booked a train to Venice. Almost there and another reason not to check luggage...thank goodness they unloaded the aircraft.

[WayneJ]

Thinking of you guys...flying from Heathrow to Venice late this evening and the pilot aborted the landing while the gear was down...always interesting. He told us later that the ATC’s diverted us at the last minute due to bad weather/runway issues. First we were supposed to divert to Bergamo and then we finally landed in Milan, where I type this post from 10C. Hope this 2hr flight doesn’t turn into 5hrs as we’ve been waiting on the runway for over an hour for a bus and they made me check luggage as I have no status on British Airways. First world problem I know.

I experienced the same scenario about a year ago. Same airports. Same airline. Same baggage situation. My luggage was delivered to my home 10 days after the trip was completed. I hope your experience differs from mine.

[Mark Kelly]

That's a lot to sort through. These guys flew for 6 minutes. Lion Air for 11 minutes. Ther's time there to come up with a plan. It's not easy to come up with a plan in a situation that's complicated by multiple failures/problems. A good read is "QF 32". It's the story written by the captain of the Quantas A380 with the uncontained engine failure that took out a whole bunch of other systems on the airplane. At one point he simply had to shift gears and quit trying to figure out what systems were lost. That didn't matter to him any more. He figured out what he still had and came up with a plan to use those systems to get back on the ground safely.

Great info and I'll read up on QF32.

FWIW "QANTAS" is an acronym so there's no U.

Queensland And Northern Territory Air Service: started out as a mail run for some of the least accessible bits of the big brown land.



Edit: having read up a bit on QF32 I'll be buying deCrespigny's book.

[SteveP]

Still haven’t heard from BA Steve, as they essentially abandoned a plane load of people at the Milan airport at 1:00am, eventually loading 7 passengers at a time into a van for a ride to a hotel...no rebooked flight news. The skeptic in me booked a hotel in Milan, took an 80 euro cab ride into the city at 2:30 am and booked a train to Venice. Almost there and another reason not to check luggage...thank goodness they unloaded the aircraft.

Good luck.. Better choice than waiting and hoping.
There is a nice hotel right at Malpensa that I have overnighted a few times to get an early am flight...an old estate converted.

[slwrnu]

weather and machines can go wrong. In a plane it is more dangerous than the bus breaking down. You have to accept this. I fly in Europe about 30 times a year. Either BA or Easyjet. I have had a few quite exciting aborted landings and diversions involving either Innsbruck, Munich, Heathrow or Gatwick. Without exception, the Flight Crew and Cabin Crew have been excellent. You have entrusted your safety to them. If the Captain/First Officer go quiet over the PA system it is because they are busy looking after you, and themselves.

[joosttx]

Question about MCAS, are there other planes that have used software to address a stability issue?

If I understand it correctly, the original 737 was designed around the long, narrow JT8D engines with cigar-like nacelles. When they stretched it and re-engined it with the higher-bypass, larger-diameter CFM56, they had to move the gearbox off the bottom of the engine for ground clearance, which gave the nacelles that distinctive flat-bottomed shape.

On the MAX, with still higher bypass and larger diameter engines, they had to move them even farther forward. Now those flat-bottomed nacelles decrease stability at high angles of attack by generating lift that's well ahead of the center of gravity. Addressed by the MCAS software.

Has there ever been another airliner with a stability issue like this, that was compensated for by software? I thought the F-16 was the first aircraft ever purposely designed with "relaxed" stability.

TH

Bring back the elegance

[SteveP]

A summary by a real journalist of the situation.

The emerging Boeing 737 Max scandal, explained - Vox

[kytyree]

It would surprise me if the 737 MAX series was the only airplane with a trim system designed to compensate for some potential inherent instability in some part of the CG range.

I think it's relatively common in the helicopter world to have an elevator that is controlled via computer and responds automatically to the present conditions. From the couple I'm familiar with it varies pretty widely how big of a deal it is if that system fails or is stuck in one extreme position or the other. But in the hovering world you usually have the advantage of not having to worry about being too slow or stalling.

I've been following the 737 Max mostly via the NYT and their articles. It's been very interesting, sadly the 737 Max and this same issue had already made the front page in between the first accident and second.

[busdriver1959]

Great info and I'll read up on QF32.

FWIW "QANTAS" is an acronym so there's no U.

Queensland And Northern Territory Air Service: started out as a mail run for some of the least accessible bits of the big brown land.



Edit: having read up a bit on QF32 I'll be buying deCrespigny's book.

That’s funny about the u. I never noticed that it wasn’t there.

[thollandpe]

A summary by a real journalist of the situation.

The emerging Boeing 737 Max scandal, explained - Vox

And more from him,
Boeing’s effort to get the 737 Max approved to fly again, explained
A bigger problem than a software update.

[SteveP]

"Should be ok, works most of the time, flying is very safe almost always..."
Boeing executives.

They need to subpoena some of the engineers and get them under oath.

[busdriver1959]

The preliminary report from Ethiopian has been out for a week. Not much is different from the Lion Air crash except that this crew was able to do the memory items for runaway trim but they had stopped flying the aircraft by that time. They never pulled the power back and about 20 seconds after stab trim cutout, they oversped the aircraft. They exceeded the max mach speed. The airloads on the control surfaces caused binding in the trim system and they couldn't move the trim manually. There's no mention of the fold out trim handle. That would've allowed more force to be applied and possibly two hands applying force. I'm assuming there's not a data recorder sensor on the handle so unless they talk about it or the investigators determine that it was out when they hit, we don't know if they used it and then stowed it.
The media reports I've seen show a lack of understanding of some pretty basic stuff by the reporters doing the writing. They only want to blame Boeing. While this is a complicated emergency, in both the Lion Air and Ethiopian crashes the crews had information that should have improved their chances of survival but they still performed poorly. Boeing shouldn't sell the airplane with the cheaper option where MCAS activates without looking at both AOA vanes. They should take that hit but Boeing didn't kill anybody, poor crew training and maintenance practices did.

[Mabouya]

They should take that hit but Boeing didn't kill anybody, poor crew training and maintenance practices did.

As is usually the case in accidents like this, it seems to be a number of different factors that combine to result in a tragedy.

Others can play the blame game and decide how much is apportioned to whom.